Refrigeration



Jan. 2, 1945. o R. c. SBQRN REFRIGERTION FiledMay 2. 1940 2 Sheets-Sheetl Y n mVENToR 0. Osborn ATTORNEY JEH 2 1945. R. c. oSBoR REFRIGERATION 2sheetsl-sneet 2 l Filed May 2, 1940 ATTORNEY u the totaldepth of thecabinet structure.

Patented Jan. 2, 1945 REFRIGERATION Ralph C. Osborn, North Canton, hio,assignor to The Hoover Company, North Canton, Ohio Application May 2,1940, serial No. 332,889

(c1. cs2-119.5)

6 Claims.

This invention relates to the art of absorption refrigeration and moreparticularly to a novel absorption refrigerating machine and an uniquearrangement thereof with respect to the cabinet of a domesticrefrigerator.

In absorption refrigerating systems of the three-fluid type andparticularly those in which the solution is circulated by a gas liftpump from the boiler to a tubular air-cooled type of absorber, adiiicult problem is presented with respect to the arrangement of thesystem in the cabinet because of the fact that the absorber forms thebottleneck of the entire refrigerating system and must be air-cooledeiliciently. All parts of the apparatus must be held within the veryrigid space limitations which are imposed upon domestic refrigeratingcabinets and which give rise to numerous difficulties in the design andinstallation of absorption refrigerating machines. Another difcultycommon to systems of the type here under consideration results from thefact that the small motor and fan used to circulate u l position suchthat a natural sounding board was formed by the back wall of the cabinetand flue, which served to amplify and distribute the inherently smallamount of noise produced by the motor fan unit. The previous arrangementof the motor fan unit also objectionablyincreased Other diiculties havearisen due to the practical impossibility of positioning therefrigerating unit in a perfectly level condition when-it is installedln a domestic establishment. Installation of the apparatus in anon-level position occasionally interfered with proper circulation ofthe soluy tion.

l It is accordingly a principal object of the present invention toprovide a three-fluid absorption short direct connections are providedbetween the various pieces of apparatus constituting the system, thatthe circulating unit is positioned in a manner to check noise producedthereby and particularly to avoid a sound board effect; thatV thesolution circulating elements are so arranged pendent of ow of airacross other portions thereof.`

More specifically, it is an object of the present invention to provide athree-fluid absorption refrigerating machine enclosed in a domesticrefrigerating cabinet embodying a storage chamber, an underlyingmachinery compartment and a rear vertically extending air duct in whichthe absorber lies in the rear portion of .the machinery compartment andslopesdownwardly and rearwardly therein whereby to provide anarrangement in which cooling air passing one section of the absorberdoes not subsequently pass another section theerof and in which the airwhich has passed any one section thereof has a free and unobstructedpath therefrom to the cooling air flue.

It is a further object of the invention to pro-p y vide an absorptionrefrigerating mechanism in which the gas circulating unit is positionedin the mechanism compartment directly beneath the food storagecompartment `and in substantially the central portion thereof.

It is a still further object of the present invention to provide anabsorption refrigerating mechanism of the type involving a gas liftcirculator for the solution circuit in which the circulator ispositioned adjacent the central portion of theA cabinet construction andin the lower part thereof whereby the same is affected to a minimumdegree by installation of the apparatus in a non-level condition. Y

It is a further object of the present invention to provide arefrigerating apparatus of the absorption type associated with a cabinetincluding a cooling chamber, an underlying mechanism chamber,` and anupstanding air duct in which an air-cooled absorber of the multipleconduit type is so arranged with respect to said mechanism chamber andduct that cooling air may ilow vertically across each conduit and maythen ow laterally to the air duct in a flow path of progressivelyincreasing cross sectional area.

Other objects and advantages of the invention will become apparent asthe description proceeds when taken in connection with the accompanyingdrawings, in which:

Figure 1 is a partial sectional side elevational view of a'refrigerating mechanism and its associated cabinet.

Figure 2 is a broken rear elevational view showing certain details ofconstruction of the apparatus, and

Figure 3 is a sectional view taken substantially on the line 3-3 ofFigure 1 and embodying also a partial section of certain apparatuspositioned in a plane below the plane of the line 3--3.

Referring now to the drawings in detail and first to Figure 1 thereof,there is illustrated a 'refrigerating cabinet I which embodies aninsulated cooling compartment 2 which is enclosed by a suitableinsulated closure 3. A machinery compartment 4 underlies the coolingchamber 2 and is closed at the front by a*l suitable removable panelelement 5 which is provided with sound insulating material 6 on its rearor inner face. The machinery chamber 4 extends beneath the insulatedcompartment 2 and also beneath the rear vertically extending air flue 'Iwhich is dened by a rear panel 8. 'Ihe entire cabinet construction restsupon a suitable foot supporting element 9 which is open to allow freeaccess of Y cooling air into the chamber 4 and iiue 1.

The top and side walls of the chamber 4 are lined with sound deadeningmaterial IIJ (see Figures 1 and 3). The panel 8 may also be lined withsound deadening material in whole or in part, if desired.

Associated with the cabinet I there is anabsorption refrigeratingapparatus of the threefluid type embodying a boiler B, an analyzer D, atubular air-cooled condenser C, an evaporator E, a gas heat exchangerGand an inclined tubular air-cooled absorber A, a liquid heat exchangerL (see Figures 2 and 3), a solution reservoir S and a gas circulatingpump'F which is driven by a suitable electrical motor M. A gas burner Hwhich is controlled by a suitable valve mechanism V is positioned toapply heat to the boiler B. The

above described elements are connected by various conduits to form aplurality of gas and liquid circuits constituting a completerefrigerating system to which reference willbe made in more detailhereinafter.

The above described system will be charged with a suitable refrigerant,such as ammonia, a

i suitable solventtherefor, such as water, and. a

suitable pressure equalizing medium, preferably a dense inert gas likenitrogen.

The application of heat to the boiler B liberates refrigerant vaporfroml the solution therein contained whichvapor thenrpasses through theanalyzer and is conveyed from the analyzer to the Vupper portion of thecondenser C by means of the conduit 29 which includes the air-cooledrectifier R. The liquid refrigerant vapor is liquefied in the condenserC and is conveyed from the bottom portion .thereof into the gas inletconduit 2l means of the conduit 22 which includes a U- shaped portionadapted `to form a pressure balancing column of liquid in order toshield the condenser from the relatively high pressureprevailing in theconduit 2|. The condenser side of the U-shaped conduit 22 is vented bymeans of a conduit 23 into the rich gas side of the gas heat exchanger Gwith which the evaporator gas discharge conduit 24 communicates.

Though the evaporator may bevof any desired type, it is herein disclosedAas being of the type in which a high velocity stream of gas circulatesupwardly through the evaporator and serves to distribute the evaporatingliquid refrigerant by Jthe frictional drag of the gas stream which is' llocatedv at the lbottom of the evaporator E by As shown herein, theevaporator conduits are encased in a suitable housing 25 in order topro- -vide an ice tray housing and the like.

28 to portions ofthe evaporator conduits and serves the purpose ofcooling the air within the chamber 2.

The enriched inert gas produced in the evaporator is discharged from theupper portion thereof by conduit 24 into the inner path of the gas heatexchanger from which it is conveyedby way of the conduit 30 to thebottom portion of the absorber A. The inert gas flows upwardlyy throughthe absorber A in counterflow relationship to absorbing solution owingdownwardly therethrough which'is supplied from a source to be describedhereinafter. The absorbing solution removes the refrigerant vaporcontent of the pressure equalizing medium and the resulting heat ofabsorption is rejected to`cooling air-flowing over the exterior walls ofthe absorber conduit A and the fins 32 attached thereto. The lean gasformed in the absorber is conveyed from the upper portion thereof intothe suction side of the gas pump F by way of the conduit 33. The inertgas is then placed under pressure by the pump VF and is dischargedtherefrom to the gas inlet conduit 2l ofthe evaporator E by wayof theconduit 34 and the outer path of the gas heat exchanger G.

The lean solution formed in the boiler B by the generation ofrefrigerant vapor is' conveyed therefrom to the solution reservoir S byway of the conduit 35, the liquid heat exchanger L, and the finnedpre-cooling conduit 3G.

The solution reservoir S is vented by means of a conduit 31 to thesuction conduit 33 of the circulating fan F whereby the solution willrise in the reservoir S to the highest level possible in the Y system.

Vthe conduit 40 and the inverted U-shaped conduit 4|, each leg kof whichcommunicates with one leg of the twin gas lift pump 39 and-below theliquid level normally prevailing therein whereby the solution iselevated into'the absorber by gas lift action. The solutionis drainedinto the pump 39 from the-reservoir S by means of a conduit 42 whichconnects to the bottom central portion of the reservoir and to thebottom bight portion of the U-shaped conduit constituting the twin gaslift pump 39.

The solution then flows downwardly through the absorber by gravity-incounterflow relationship with the pressure equalizing medium refrigerantvapor mixture which is flowing upwardly therethrough. As describedheretofore, thesolution absorbs refrigerant and the resulting richsolution isvlconveyed from the bottom portion of the absorber A to theupper portion of theV analyzeriEi-by way of the conduit 45, the liquidheat exchanger L, and the conduit 46, thus completing the absorbingsolution circuit.

The arrangement of the apparatus with respect to the cabinet constitutesan important feature of the present invention and will now be described.

The rear wall of the chamber 2 Vis provided with an openingl 50 which isarrangedto be closed by a suitable insulated panel I and a joint sealinggasket construction 52. The size of the opening 50 and the panel 5| aresuch that the evaporator E and its associated control mechanism 52 maybe freely inserted into the compartment 2 through the opening 50.

The panel 5| will be made rigidly with the evaporator and other elementsof the refrigerating mechanism so that the entire apparatus may beassembled with the cabinet as a unit. The apparatus will be controlledby means of a suitable adjustable control mechanism illustrated as acontrol box on top of the evaporator E at 52. The control mechanism 52will have suitable connections to the solenoid gas valve V and to thecirculating motor M whereby to energize the motor and gas burner inresponse to a demand for refrigeration and to de-energize these elementswhen the refrigerating demands are met. nism 52 and the elements M and Vhave not been shown as they per `se form no part of the pres- Theconnections between the mecha? positioned in theright hand corner of thecompartment 4, as viewed in Figure 3, with the analyzer, which is thetallest part of this assembly, positioned forwardly of the absorber.Consequently, that portion of the boiler-analyzer liquid heat exchangersystem which will underlie a small end portion of a few of the forwardabsorber tubes underlies those tubes which are at Another feature ofthis arrangement is that the heater H and gas `valve V are positionedremotely rom the absorber tubes and .the path of cooling ent invention.A preferred form of control mech'- anism is disclosed and claimed in theco-pending application of Curtis C. Coons, application No. 148,424,filed June 16, 1937.

As is illustrated, the gas heat exchanger is par-4 air and,additionally, these elements are in the v veryfront portion of thecompartment 4 whereby tially embedded in the rear wall of the chamber" 2and in the panel 5l whereby to leave the air flue 1 substantiallyunobstructed.

The absorber A comprises a plurality of generally parallel reverselyinclined and serially connected conduits 55, each of which is providedwith' a plurality of heat rejecting fins 32 which are offset upwardlyfrom the tubes in the direction of air ow thereacross. The absorber as awhole slopes downwardly and rearwardly to the lowest tube 55,

from the highest tube 55 which lowest tube terminates adjacent the panel8 beneath the flue 1 but in the mechanism com'- partment 4.

The cooling air which enters the bottom portion of the chamber 4 risessubstantially vertically, crosses the tubes 55 and their associated ns32, and then turns to the right, as viewed I in Figure 1, in the case ofthe`three highest tubes 55, in order to enter the cooling flue 1. Itwill be noted that the quantity of air which has passed the absorberwill increase as one progresses from left to right of the chamber 4, as

viewed in Figure 1. Consequently, the quantity of air flowing towardsthe bottom of the flue 1 constantly increases from left to right, asviewed in Figure 1. However, the cross sectional area of the spacebetween the absorber A and the bottom wall of the chamber 2 -constantlyincreases as one progresses from left to right, as viewed in Figure 1,wherefore provision is made for the air added by each of theprogressively lower absorber tubes and there is no tendency for airwhich has traversed one tube and its associated fins to come intocontact with a subsequent and lower absorber tube and its ns; also asthe quantity of air discharged from the absorber progressivelyincreases, the cross-sectional area of the space provided to handle thisair progressively increases wherefore there is no tendencyto choke theair ow above the absorber, all absorber tubes receive their properproportion of the total air flow and all receive air'not previouslyheated by passage across an absorber tube.

The boiler-analyzer and liquid heat exchanger assembly is embedded in ablock of insulating material and the whole of this assembly is the samemay readily be reached for servicing, adjustment, and the like simply byremoving the front panel 5. It is also of` importance in this connectionthat the burner and those portions of the boiler-analyzer system whichare adjacent the burner are remote from the path of air flow of theabsorber, consequently these elements which form the hottest parts ofthe entire system are arranged so that they will not interfere withabsorber cooling.

The products of combustion discharged by the burner H pass through acentral flue 6| of the boiler and are then conveyed to the top portionof the duct 1 by means of a conduit 62, preferably insulated, whichextends upwardly in one corner of the air duct 1. It is apparent fromFigures 2 and 3 that the products of combustion discharge conduit 62 isso positioned that the same is never in a direct path of air flowingover either the absorber or the condenser.

The motor fan unit is positioned in the top central portion of thecompartment 4| directly beneath the sound insulating panel Wand issurrounded on three sides by sound insulated panels. This arrangementhas been found to muflle any noise created by the motor fan uniteffectively, thus eliminating a commercial objection to this typemachine.

Another important result obtained by this arrangement of the absorberand circulator is that the circulating fan is removed from the flue lwhich has been the conventional position in prior arrangements. Byremoving the circulating unit from the flue- 1, the depth of that lluemay be materially decreased as the depth required to accommodate thecooling air flow is considerably less than the depth required to housethecirculating unit. Consequently, an effective reduction in the overalldepth of the unit is achieved without sacrificing either efficiency orfunction and any depth saved at this point is of material importance inenabling the designer to t the cabinet within the maximum dimensionsallowable in household machines.

Due to the fact that it is very difficult if not impossible to insurethat the machines will be in an absolutely level position when installedin a household, the present invention provides an the solution reservoirand twin gas lift pump adjacent the rcentral portion of the compartment4 and further by'taking the liquid to be pumped from the bottom centralportion of the solution reservoir that the inequalities normallyencountered in domestic establishments .will not adversely affect thetwin gas lift pump and specincally will not cause sufficient vdifferencein the liquid levels inthe two legs of thepump to pre-y vent the samefrom operating properly. It is not necessary to place these elements inthe geometrical center of the compartment 4 because of the fact that thesmall inclination which may be given the part located adjacent thecenter due to an inequality of the apparatus is not sufficient to causeinjurious effects from the operation of the System, whereas suchinequalities wouldproduce this result were the gas lift pump, forexample, positioned in one corner of the compartment 4.

vThe refrigerating mechanism is carried upon a suitable frame mechanismindicated generally at 1U which rests upon and is suitably attached tothe foot plate 9.

Thus, the present invention provides a refrigerating apparatus in whichthe circulating pump and solution reservoir are positioned in thecentral portion of the mechanism compartment whereby noise produced bythese elements is effectively muiiled within the compartment' and theapparatus is protected from undesirable-results which might iiow frominstallation of the rame in a non-level position.

The arrangement of the absorber, that is, inclined downwardly `andrearwardly within the compartment 4 to a position beneath the lower endof the air iiue 'l facilitates this by allowing the gas lift pump andsolution reservoir Aand circulating fan and its drive motor to be movedout of the. normal path of cooling air through the apparatus andftoprovide an unobstructed path of flow of cooling air from a 4pointadjacent the door upwardly through the compartment 4 and over theair-cooled absorber A. Still further the arrangement of the air-cooledabsorber A provides a path rearwardly of the compartment 4 and above thelevel of the absorber of constantly increasing cross-sectional area forair heated by passage over the absorber element which is then seeking anentrance to the flue 'I Wherefore all the absorber tubes receive air notpreviously heated by passing over another absorber tube, are notobstructed by mechanical elements of the apparatus andthe absorber is soarranged with respect to the chamber 4 and particularly the bottom wallof the compartment 2 that there is no choking eifect on the air streamdischarged by the absorber element.

Moreover, the flue 1, though narrow in depth as compared with previousconstructions, -is

ample to takecare of the quantity of air necessary to cool the apparatusadequately and is substantially unobstructed for its entire depth exceptfor normally air-cooled elements. These factors all permits short directconnections between all parts of the apparatus located within themechanism compartment.

While the invention has been described and i1- lustrated in detail,various changes may be made in the arrangement, construction andproportion of parts without departing from the spirit of, the inventionor the scope of the appended claims.

I claim:

1. In a refrigerating apparatus, a cabinet having a storage chamber andan air cooling and mechanism chamber extending beneath and along onewall of said storage chamber, a three-fluid absorption refrigeratingsystem associated with said cabinet including an evaporator in said"storage chamber and an absorber, a generator and a condenser in saidmechanism compartment connected in circuit, a power driven circulatorconnected to circulate an inert gas between said evaporator and saidabsorber, said power driven circulator being located in said mechanismcharnber beneath said storage chamber adjacent the central portionthereof to reduce the effect of noise produced by said circulatorexternally of said cabinet, and sound absorking material on y certain ofthe walls of said mechanism chamber.`

2. In a refrigerating apparatus, a cabinet having a storage chamber andan air cooling and mechanism chamber extending beneath and along onewall of said storage chamber, a threefluid absorption refrigeratingsystem associated with said cabinet including an evaporator in saidstorage chamber and an absorber, a generator and a condenser in saidmechanism compartment connected in circuit, a gas lift pump in saidcircuit arranged to circulate solution between said generator and saidabsorber, said pump being located in said mechanism chamber beneath saidstorage chamber and adjacent the central portion thereof wherebydeviations from level installation of the apparatus will have a minimumeffect on said pump.

3. In arefrigerating apparatus, a cabinet having a storage chamber andan air cooling and mechanism chamber extending beneath and along onewall of said storage chamber, a three-fluid absorption refrigeratingsystem associated with said cabinet including an evaporator in saidstorage chamber and an absorber, a generator and a condenser in saidmechanism compartment connected in circuit, a4 gas lift pump in saidcircuit arranged to circulate solution between said generator and saidabsorber, a solution reservoir connected to the inlet of said pump, saidpump and said reservoir being located in said mechanism chamber beneathsaid storage chamber and adjacent the central portion thereof wherebydeviations from level installation of the apparatus will have a minimumeffect on said pump.

4. A refrigerating device comprising a cabinet structure including arefrigerating chamber and a mechanism' compartment having a lowersection underlying said chamber and arranged for free flow of coolingair thereinto` from below and an upsta'nding section opening into saidlower section, an absorption refrigerating apparatus associated withsaid cabinet structure comprising an inert fluid circuit including anevaporator'in said chamber and an absorber in said compart.

ment, an absorbing fluid circuit including said absorber and a generatorpositioned in said compartment and means for liquefying refrigerantvapor produced by said generator and for supplying the liquid to saidevaporator, and a power driven circulator included in said inert fluidcircuit and positioned in said compartment beneath the central portionof said refrigerating chamber and above said generator.

5. A refrigerating device comprising a cabinet structure includingarefrigerating chamber and a mechanism compartment having a lower sectioni underlying said chamber and arranged for free ow of cooling airthereinto fromA below and an upstanding section opening into said lowersection, an absorption `reirigerating apparatus associated with saidcabinet structure comprising an inert gas circuit including anevaporator in said chamber and an absorber in said compartment, asolution circuit including said absorber and a generator positioned insaid compartment, means for liquefying refrigerant vapor produced bysaid generator and for supplying the liquid to said evaporator, asolution reservoir in said solution circuit, and a gas lift solutioncirculating pump in said solution circuit, said pump being connected toreceive solution from the bottom central portion of said reservoir and`to discharge solution into said absorber, said pump and said reservoir`being located adjacent the cent1-a1 portion of that section of saidcompartment which underlies said chamber.

6. A refrigerating device comprising a cabinetl structure including arefrigerating chamber and a mechanism compartment having a lower secfreeflcwofcooling ar thereinto from below and an upstandlng secti n openinginto said lower section, an absorpt on refrigerating apparatusassociated with said cabinet structure comprising an inert gas circuitincluding an evaporator in said chamber and an absorberin saidcompartment, a solution circuit including said absorber and a generatorpositioned in said compartment, means for liquefying refrigerant vaporproduced by said generator and for supplying the liquid to saidevaporator, said absorber comprising a plurality of conduits positionedat different elevations, said conduits as a group extending from a pointbeneath said chamber downwardly in the direction of said upstandingsection of said compartment, a power driven circulator included inA saidinert gas circuit and positioned in said compartment beneath saidchamber, a solution reservoir in said solution circuit, and a gas liftsolution circulating pump in said solution circuit, said pump beingconnected to receive solution from the bottom central portion of saidres-r

